Feed regulator for lubricating systems



Aug. 27, 1929. w MATHEWS 1325,812

FEED REGULATOR FOR LUBRICATING SYSTEMS Filed Jan. 6, 1927 3 Sheets-Sheet 1 '70 l/lYLOADEf? 5x51 III I v Ea IVA -n= Gnome 1929. w. E. MATHEWS 1,725,812

FEED REGULATOR FOR LUBRICATING SYSTEMS Filed Jan. 6, 1927 3 SheetsSbeet 2 JJI 33 -i 6' f 4 II 2 4'3 44- 27 I 4 55 47 I 37 2 I I V a 8 9 \5Z 9mm 45% v -1, 1 T/Wlliamli'. Mathews 46% 50 40 I Z 25 24 (m Aug. 27, 1929. w. E. MATHEWS FEED REGULATOR FOR LUBRICATING SYSTEMS I5 Sheets-Sheet Filed Jan. 6, 1927 vweuto: Mh'lliamE. Mathews Cir Patented Aug. 27, 1929.

UNITED STATES PATENT OFFICE.

WILLIAM E. MATHEWS, OF BIRMINGHAM, ALABAMA, ASSIGNOR TO HARDIE-TYNES MFG. 00., 0F BIRMINGHAM, ALABAMA, A CORPORATION OF ALABAMA.

FEED REGULATOR FOR LUBRICATING SYSTEMS.

Application filed January 6, 1927. Serial No. 160,010.

This invention has general reference to lubricating systems, and relates more particularly to such systems in which the rate at which the lubricant is fed is variable, and is regulated automatically.

Especially in connection with air c0mpressors and the like, by which air, gases or other fluids are compressed, for the purpose of em .-loying them for power transmission, for ot ier use, or for subsequent chemical or other treatment, it is extremely important that the rate at which lubricant is supplied to the cylinder or cylinders in which compression takes place, shall vary according to changes in the pressure created at different times at one or more points in the compression system, and according to temperature changes at such point or points; also, that such regulation of lubricant supply shall be automatic, efficient and dependable. Thus, in the use of air and compressors it is considered the best practice to avoid the creation of excessive pressures or temperatures in the cylinders, or elsewhere in the compression system, by employing unloading apparatus adapted to discharge the excess volume of air or gas that has been drawn into the cylinders, over and above that which it is desirable to compress, and has become heated to some extent,following which the cylinders are refilled with cooler air or gas drawn from the source of supply; and the lubricating system should respond automatically to the variations of pressure and temperature that occur before, during and after such unloading operations, as well as at other times.

A primary object of the present invention is to provide an automatic lubricatingsystem for power units and other mechanisms, in which the rate at which the lubricant is fed varies with changes in the application of the energy supplied by the source of power.

A further object is to provide such a lubricating system in which the rate at which the lubricant is fed varies with temperature changes in parts of the mechanism orapparatus with which said system is employed.

Another object is to provide an automatic lubricating system for power units which supply power through a fluid medium, and in which the rate at which the lubricant is fed varies with changes in the pressure in such medium.

A further object is to provide an automatic lubricating system for power units which sup ply power through a fluid medium, and in which the rate at which the lubricant is fed varies with changes in the temperature of such medium.

A further object is to provide an automatic lubricating system for power units which opcrate at a substantially constant speed, in. which power is supplied through a fluid medium, and in which the rate at which the lubricant is fed varies with changes in the pressure in such fluid at different points.

And a still further object is to provide an automatic lubricating system for power units which operate at a substantially constant speed, in which power is supplied through a fluid medium, and in which the rate at which the lubricant is fed varies with changes in the temperature of such fluid medium at different points.

The means by which the foregoing and other objects are accomplished by my inv'em tion, and the manner of their accomplishment, readily will be understood from the following description on reference to the accompanying drawings, which depict preferred embodiments of the invention, and in which Fig. 1 is a diagrammatic side elevation of a two-stage, motor-driven air compressor,

having my improved feed regulator applied to the lubricating system thereof.

Fig. 2 is an enlarged fragmentary detail view of the regulator for the force-feed lubricator, in section substantially on the line II II of Fig. 3.

Fig. 3 is an enlarged fragmentary detail view of the regulator and parts of thelubricator, in section substantially on the line III-III of Fig. 2.

Figs. 4;, 5 and 6 are diagrammatic views illustrating different operating positions of parts of the regulator.

Fig. 7 is a diagrammatic View illustrating a preferred manner of employing the regulatorin connection with a three-stage compressor.

Fig. 8 is a sectional view of a spring controlled check valve employed with my in-' Vention.

As illustrated in the drawings, and referring first to Figs. 1 to 6 inclusive, Fig. 1 shows diagrammatically a side elevation of a two-stage, motorsdriven air compressor, the view being taken at the low-pressure side. The shaft 9 of the motor 10. 5 extended into the space in the frame 11 occupied by the crosshead guides (not shown), and to said shaft is secured the crank 12 from which the connecting-rod 13 extends to the cross-head 14, which is connected by the piston-rod 15 with the piston 16, reciprocable in the lowpressure air-cylinder 17. From said cylinder the compressed air passes through a pipe 18 into the inter-cooler 19, and thence to the high-pressure air-cylinder (not shown). All of the parts thus far referred to, and their arrangement, are common and WBllk11OWIl in the air-compressor art, and a more detailed description thereof is therefore not thought necessary herein.

A pin 20 projects from the crank 12, eccentrically of the motor shaft 9, and has rotatably secured thereon one end of a rod 21, the other endof which is pivotally connected with one end of a lever 22 which is fulcrumed on a pin 23 projecting fromthe side of the frame 11, there being pivotally secured to the other end of said lever one end of a rod 24, the other end of which is pivotally secured to the actuating arm 25 (see Fig. 2) of the regulator 26 for the force-feed lubricator 27, said regulator and said lubricator being mounted together upon a suitable bracket 28, which is secured to the frame 11. From the lubricator 27 a pipe 29 leads to the point or points at which the lubricant is to be delivered, and an air-pipe 30 leads from a suit able point of connection with the compressedair system, and communicates through two spring-controlled check-valves 31 (only one of whichis shown) with pipes 32 and 33, each of which has a ball check valve 34 therein, and leads into a pipe 35 communicating with the air-pressure cylinder 36 of the regulator 26. The valve 31 is shown in detail in Fig. 8, and its operation will be readily understood without a detailed description. Pipes 32 and 33 are extended above the spring-controlled check-valves 31, and supply air at different pressures to operate the unloader system (not shown) at suitable points as well as supply air for the variable operation of the lubricating system.

Referring now to Figs. 2 to 6 inclusive, it will be seen that the air-pressure cylinder 36 of the regulator is secured upon a housing 37 by two similar studs 38, each having placed thereover a helical compression spring 39, and said springs being interposed between the bottom 40 of said housing and a bearing 41 whiclris slidably mounted on the two studs 38, and has projecting centrally from its upper face a cylindrical piston-rod 41 which is lifted slidably in an opening provided therefor in the top 42 of the housing 37 and has secured at its upper end a plunger 43 which fits slidably in the air-pressure cylinder 36, and is provided with suitable piston-rings 44. Between the studs 38, and placed centrally thereof, in line therewith and parallel thereto, a studbolt 45 projects up wardly from the bottom 40 of the housing 37, the distance of such projection above said bottom ordinarily being approximately onehalf that from said bottom to the sliding bearing 41 when said bearing is in its uppermost position, and said studbolt has placed thereover a helical compression spring 46, the length of which when uncompressed is considerably greater than that of said studbolt.

The housing 37 is open at the side which is directed toward the lubricator 27, and ad jacent said opening the floating lever 25, which serves as the actuating arm for the regulator, has its upper end pivotally cured to the sliding bearing 41 by means of a pin 47, while at its lower end said lever is pivotally connected by means of a pin 48 with one end of the rod 24, the other end of which is pivotally connected with the lever 22 fulcrumed on the frame 11. A slot 49 extends longitudinally of the floating lever 25, on the center line thereof, and slidably mounted in said slot is a block 50, which is pivotally connected by means of a pin 51 with the lower end of the operating lever 52 of the lubricator 27, said lever having its upper end fast on a shaft 53, which extends into the interior of the lubricator casing and has secured at its inner end a pawl 54 adapted to co-act with a ratchet 55 for operating the lubricator mechanism.

When the pressure of the air enteringthe upper part of the air-pressure cylinder 36 through the pipe 35 isinsufficient to force the'plunger 43, and hence the sliding bearing 41, downward, thereby compressing the springs 39, and the parts of the regulator are therefore in the positions indicated in Figs. 2, 3 and 4, maximum movement is imparted to the driving lever 52 of the lubricator, through the floating lever 25 and the rod 24, and the lubricant is accordingly fed the maximum rate. )Vhen, however, the air pressure upon the plunger 43 is suflicient to force the sliding bearing downward to any extent, and thereby to move the pin 47, on which the floating lever 25 is fulcrumed, closer to the pin 51 which connects said lever with the operating lever 52 of the lubricator, while at the same time moving the pin 43, which connects the lower end of the floating lever with the rod 24, farther away from the pin 51, (such conditions being indicated in Fig. 5) the movement imparted to the operating lever 52 of the lubricator, and hence the rate at which the lubricant is fed, is correspondingly lessened. The opposition offered by the two springs 39 to downward movement of the sliding bearing 41, gradually increases as said bearing is moved downward, and further opposition to such downward movement results from engagement of said bearing with the third spring 46. Thus, both gradually-increasing and step-increasing opposition to downward movement of the sliding bearing i1 is provided, and the arrangement just described may readily be varied to suit diilerent conditions, as by using only one of the springs 39 and placing it over the central stud, so that only gradually-increasing opposition will be offered to downward movement of the sliding bearing, or by using all three springs and having one of the springs 39 shorter than the other one thereof butlonger than the spring 46, so that there will be two step-by-step increases in the resistance of the springs to compression, in addition to gradual increase before the first step, between the first and second steps, and after the second step. The motor which I prefer to employ for operating the air compressor, is of the induction type, and therefore its speed is substantially constant, so that there is no appreciable variation in the rate of movement of the floating lever 47 by the rod 2 1, and hence the rate at which the lubricant is fed nor mally varies only at the result of movement of the sliding bearing 41.

In Fig. 7 the air compressor, for purposes of illustration only, is shown diagrammatically as having its three cylinders arranged in tandem, but ordinarily a three-stage compressor has two of its cylinders placed in tandem, and the other cylinder placed parallel therewith. The three pistons (not shown), for the low-pressure cylinder 56, the intermediate cylinder 57 and the hi 'h-pressure cylinder 58, are driven from an induction motor 59, and the rod 60 for swinging the floating lever of the regulator 61 for the force-feed lubricator 62 is reciprocated through an eccentric connection with the motor shaft,-all in substantially the manner described hereinbefore in connection with Fig. 1. Air compressed in the lowpressure cylinder 56 is delivered into an inter-cooler 63, whence it is drawn into the intermediate cylinder 57 is again compressed therein and discharged into an inter-cooler 642, from which it is drawn into the highpressure cylinder 58, and after the third stage of compression passes to the point of delivery through a suitable pipe 65. Three spring-regulated check-valves 66, 67 and 68 are moutned upon a common bracket 69 which is secured in any preferred position upon the frame of the compressor. From the inter-cooler 63 a pipe 70 leads to the springregulated cheek-valve 68, and similarly a pipe 71 leads from the inter-cooler 64: to the check-valve 67 and a pipe 72 leads from the delivery pipe to the check-valve 66. From the three spring-regulated check-valves, individual pipes 73, each having a ball-check valve 74: therein, lead to a pipe 7 5 which communicates with the air-pressure cylinder of the regulator 61. By adjustment of the respective regulating springs of the three check-valves, 66, 67 and 68, said valves are set so as to open, and to permit the passage of compressed air therethrough to the airpressure cylinder 36 of the regulator 26, at predetermined pressures dependent upon the pressures intended to be developed in the parts of the compression system from which the pipes 7 O, 71 and 72 lead. When the air pressures in the pipes leading to said checkvalves are insuflicient to open them, and thus to permit the passage of the compressed air therethrough and to the air-pressure cylinder 36 of the regulator 26, the lubricant is fed at the maximum rate for which the regulator and the lubricator are set, but when the pressure in any one of said pipes is sufficient to overcome the resistance of the spring in the check-valve to which that particular pipe leads, and to depress the sliding bearing 41 of the regulator, the rate at which the lubricant is fed is lessened accordingly. The speed of the motor, and the sizes of the cylinders and other parts of the compression system, are so co-related that the air or other fluid in the inter-coolers and in the terminal delivery pipe is intended to be maintained at predetermined pressures under predetermined temperatures, and, manifestly, if such predetermined temperature is exceeded at any point in the compression system, the predetermined pressure at such point will be exceeded to a corresponding extent. When compressing air, or other fluids having an oxidizing or carbonizing content, and particularly when the extent of compression is high, it is of the utmost importancethat the temperature of the compressed substance be' kept below the point at which flash or eX- plosion, or excessive carbonization of the lubricant employed, may result, and that, in the event that such excessive temperatures are reached, the amount of lubricant exposed thereto shall be minimized. By my improved means for regulating the rate at which the lubricant is supplied, said rate is regulated automatically in accordance with the pressure at various points in the compression system, and, due to the relation between pressure and temperature in air and other fluids, is likewise regulated in accordance with the temperatures at such points. It should be noted that such regulation is not dependent upon the rate of speed of, or the amount of work done by, the power-supply unit, but upon the disposition made of the energy supplied by such unit. For example, if the pressure in one of the inter-coolers, or in the terminal delivery pipe, of a com pressor be reduced by operation of the unloading system, or otherwise, the rate at which the lubricant is fed will be increased automatically, regardless of whether the power-supply unit be operating at full-load or at partial-load; and, likewise, if the pressure or the temperature at any such point exceed a predetermined amount, the rate of feed of the lubricant Will be lessened, regardless of the amount of Work being done by the power-supply unit.

Various modifications of minor details of the invention disclosed herein doubtless readily Will occur to those skilled in this art, but such modifications fall Within the scope of my inventive rights, and my invention is not to be construed as being limited to any details not specifically set out in the claims.

Having now fully disclosed the invention, What I claim as new, and seek to secure by Letters Patent. is:

1. In a fluid-compression system, the combination of a feeder for distributing lubricant to parts of said system, means for supplying different pressures to different points in the system, and means for varying step by step the rate of lubricant-feed in accordance With the variations in the pressures at diiferent points in said system.

2. In apparatus for compressing fluids, the combination, With a source of power and a compression chamber, of a lubricant-feeder, valves operable responsive to variations in pressure in the chamber to provide different pressures, and means for regulating step by step the operation of said feeder responsive to operation of said valves.

3. In apparatus of the character described, the combination, With a source of power, a chamber in Which fluid is compressed by operation of said source of power, and a container for lubricant, of means for feeding lubricant from said cont-amer, means dependent upon the pressure in said compression chamber for regulating the operation of said lubricant-feeding means and spring controlled check valves for supplying step by step variations in pressure to the last mentioned means.

4. The combination, with a fluid-compressor having an unloading system connection, of a lubricant-feeder, means for supplying pressure to the connection in predetermined steps, and means for regulating the operation of said feeder by the pressure supplied to said connection.

5. The combination, with a fluid-compressor having a plurality of unloading system connections, of means for supplying air at different predetermined pressures to said connections, a lubricant-feeder, and means for regulating the operation of said feeder step by step by the pressures supplied to the unloading system connections.

6. The combination, with a fiuid-compres sor having a plurality of unloading system connections, and a substantially constant speed prime mover for operating said compressor, of means for supplying air at difierent predetermined pressures to said connections, means for feeding lubricant to said compressor, and means connected With said unloading system connections for automatically varying the rate of such feed in steps according to the pressure in said connections during the substantially constant-speed operation of said prime mover.

In testimony whereof I afiix my signature.

WILLIAM E. MATHEWS. 

